Cubs historical sleuthing: Two franchise icons

The photo at the top of this post shows, of course, Ron Santo and Ernie Banks, Hall of Famers both, two of the best and most beloved players in Cubs history.

But when was this photo taken? Santo and Banks were teammates for 12 seasons, from 1960 through 1971.

Click here for a larger version of the photo, and you can play along while I sleuth this one out.

There are a number of clues. I’ll start with the ballpark; the railings are in the lower box seat area and the corner seats have not yet been angled toward the plate. That would date this right away to before 1968. (Incidentally, look at the concrete panels behind the seating area, originally installed in 1958 but now completely removed. When…